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Xiaoqi Guo Yuanpeng Hao Wenying Zhang Fei Xia Hongtong Bai Hui Li Lei Shi 《Molecules (Basel, Switzerland)》2022,27(19)
Origanum vulgare L. (oregano) is an aromatic plant with wide applications in the food and pharmaceutical industries. Cronobacter sakazakii, which has a high detection rate in powdered infant formula, adversely impacts susceptible individuals. Oregano essential oil (OEO) is a natural antibacterial agent that can be used to fight bacterial contamination. Here, OEO chemical compounds from eight oregano varieties were analyzed by gas chromatography–mass spectrometry and their antibacterial properties were assessed. The eight OEOs were clustered into two groups and were more diverse in group 2 than in group 1. Six compounds, including p-cymene, 3-thujene, γ-terpinene, thymol, carvacrol, and caryophyllene, were shared by eight OEOs. Among the eight oregano varieties, OEOs from O. vulgare sc2 had the strongest antibacterial activity against C. sakazaki, with the inhibition zone of 18.22mm. OEOs from O. vulgare jx, O. ‘Nvying’, O. vulgare ‘Ehuang’, and O. vulgare ssp. virens were also potent. Moreover, the antibacterial activity of OEOs was positively correlated with the relative content of thymol. As the main OEO antibacterial compound, thymol affected the normal growth and metabolism of C. sakazakii cells by destroying the bacterial membrane and decreasing the intracellular ATP concentration. Thus, in light of the antibacterial activity detected in the OEOs from the eight oregano varieties, this study provides a theoretical foundation for oregano cultivar management and development. 相似文献
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《Angewandte Chemie (International ed. in English)》2017,56(36):10933-10937
Owing to the environmental hazards arising from sulfur‐containing combustion products, strong legal regulations exist to reduce the sulfur content of transportation fuels down to a few ppm. With the ongoing depletion of low‐sulfur crude oil reservoirs, increased technological efforts are needed for crude oil refining to meet these requirements. The desulfurization step is a critical part of the refining process but partly suffers from the recalcitrance of certain species to sulfur removal and the inability to quantitatively understand the behavior of individual compound classes during the process. We herein present a new and simple approach for the parallel quantification of three different classes of sulfur species present in crude oils by LC separation and on‐line detection and quantification by ICP‐MS/MS. This approach will help to estimate the amount of recalcitrant species and thus facilitate the optimization of desulfurization conditions during fuel production. 相似文献
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气相色谱/化学电离-质谱法检测石油中的环烷酸 总被引:8,自引:0,他引:8
采用柱色谱和阴离子交换树脂法分离出原油200~420 ℃馏分中的羧酸,通过红外光谱仪检验分离效果及分离出的羧酸的类型。采用气相色谱及以异丁烷为反应气的化学电离(CI)质谱法分析分离出的羧酸。在对其结构进行推断和归类中,以纯脂肪酸、环烷酸以及分离出的石油酸的CI质谱数据为基础,结合环烷酸z系列通式CnH2n+zO2,分别得到了不同碳数的脂肪酸及一环、二环……六环环烷酸的分析结果。结果表明,含酸原油中的羧酸主要是环烷酸,相对分子质量分布为170~510,碳数分布为C10~C35,其中双环、三环环烷酸含量较高。 相似文献
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基于费谢尔判别法的原油、燃料油鉴别技术研究 总被引:2,自引:0,他引:2
对原油、燃料油的鉴别方法进行了研究.以来自不同国家和地区的30个原油样品以及不同产地、不同种类的24个燃料油样品中的正构烷烃(n-C7~30)、植烷(Ph)、姥鲛烷(Pr)的含量构成训练集.借助SPSS 16.0进行费谢尔(Fisher)判别分析,建立Fisher判别函数.将判别变量值代入后,得到样本的空间位置,再计算样本至各组重心的距离,据此判断分类情况.结果表明,Fisher判别法可以很好地用于原油和燃料油的鉴别,具有快速、准确等特点. 相似文献
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随着工业的发展,油水污染日渐严重,特别是石油的泄露、有机化学品的排放对生态环境造成了难以挽救的损害。因此,开发新型高效的油水分离材料与技术是一个极为重要的任务。特殊润湿性油水分离材料的出现,为科研人员指明了道路。本文以用于油水分离的特殊润湿性材料为研究体系;首先,对具有特殊润湿性油水分离材料的基本理论和设计理念进行分析;然后介绍了通过调控材料表面的微观结构和表面化学组成制备特殊润湿性材料实现不同的油水分离效果的研究进展,并且尝试从微纳米尺度上揭示特殊润湿性材料的特征,形成从微纳米尺度上揭示油水分离用材料化学品结构特征的技术基础。最后指出了目前在油水分离用功能材料化学品这一领域存在的一些问题,并对这一领域的发展趋势进行展望。 相似文献
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Yanting Wang 《Journal of Dispersion Science and Technology》2014,35(9):1255-1263
The thixotropy of three waxy crude oils was measured to evaluate different measurement methods using RheolabQC. The results showed that the average relative deviation using the hysteresis loop method was 24.4%, the lowest among the methods evaluated. The method of stepwise-increase in shear rate was able to obtain several rheological characteristics from a single experiment, and such a thixotropic experiment can be performed with any rheometer. This makes the stepwise-increase in shear rate the method of choice when considering convenience. However, the method of hysteresis loop is preferable when it comes to the reliability of measuring thixotropic parameters. 相似文献
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马山前胡挥发油化学成分研究 总被引:5,自引:0,他引:5
本文用毛细管气相色谱、气相色谱/质谱/计算、气相色谱/红外光谱等现代仪器分析技术,对马山前胡挥发油的化学成分进行了分析研究,从毛细管色谱分离出80多个峰,确认了其中37种成分,占色谱总馏出峰面积的97%以上,该挥发油的主要化学成分为蒎烯。 相似文献
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油藏化学工程是以三次采油为背景,在油藏工程和化学等相关学科的交叉领域中发展起来的,它主要是研究油藏环境中发生的传递现象和化学反应,及其影响油藏动态的原理与规律的学科。化学工程中一系列的新方法、新概念、新的理论原理的应用对油藏化学工程学科的形成将起到重要的推动作用,同时化学工程的发展与我国独特的自然资源和社会经济背景相结合将使其具有更强大的生命力。油藏化学工程研究的复杂环境和丰富的学科营养,为发展化学工程的前沿领域提供了广阔的园地。 为了更好地推进我国油藏化学工程研究的发展,文中提出了还需要加强的有关工作。 相似文献
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M. V. Kök 《Journal of Thermal Analysis and Calorimetry》1999,56(2):947-951
This paper investigates the minimum oil content necessary for self-sustained combustion, which is introduced as a criterion
for the selection of suitable reservoirs for in-situ combustion processes. Differential scanning calorimetry was used to determine
the heat values of oil-limestone mixtures. The minimum temperature required for the total consumption of the fuel was obtained
by thermogravimetry (TG/DTG). The minimum amount of oil necessary to sustain combustion was calculated from these two parameters
and compared with the oil content of the reservoir. Reservoirs with an oil content greater than or equal to this minimum value
were considered feasible. It was seen that the fields examined are generally not suitable for in-situ combustion processes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Prickly pear (Opuntia ficus-indica L.) is a member of the Cactaceae family originally grown in South America, and the plant is now distributed to many parts of the world, including the Middle East. The chemical composition and biological activities of different parts of prickly pear, including cladodes, flowers, fruit, seeds and seed oil, were previously investigated. Oil from the seeds has been known for its nutritive value and can be potentially used for health promotion. This review is an effort to cover what is actually known to date about the prickly pear seeds oil extraction, characteristics, chemical composition and potential health benefits to provide inspiration for the need of further investigation and future research. Prickly pear seeds oil has been extracted using different extraction techniques from conventional to advanced. Chemical characterization of the oil has been sufficiently studied, and it is sufficiently understood that the oil is a high linoleic oil. Its composition is influenced by the variety and environment and also by the method of extraction. The health benefits of the prickly pear seed oil were reported by many researchers. For future research, additional studies are warranted on mechanisms of action of the reported biological activities to develop nutraceutical products for the prevention of various chronic human diseases. 相似文献
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用碱抽提法从大庆原油中分离石油羧酸,通过硅胶柱层析法将石油酸分为5个不同的馏分,分别对3个极性馏分的甲酯化产物进行GC-MS结构鉴定,大庆原油含有C9-C24全部系列正构饱和脂肪酸、多种异构饱和脂肪酸及不饱和脂肪酸,乙酸乙酯馏分在整个洗脱分离物中的量占最大比例,而且几乎集中了所有的异构脂肪酸。 相似文献
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Habibu Uthman 《Journal of Dispersion Science and Technology》2013,34(4):609-615
In this work, a corrosion prediction mathematical model for risk assessment in oil and gas production and transportation facilities has been created. This work focuses on partial pressure of carbon (iv) oxide, CO2 and the operating temperature in process equipment and transportation facility pipes as a function of corrosion rate. The model equation formulated was based on the principle of multiple linear regressions of data. The final model representing the corrosion rate of crude oil equipment was obtained CR = b o + b 1 T + b 2 P (CO 2). The model was simulated using polymath software. The correlation between the experimental and simulated resulted obtained using root mean square deviation (coefficient of determination) was 99.74% which is high, suggesting that the relationship between the predictor and response variables is linear. The variation in the model equation is 0.0066374. This low value of the variance shows that the model is accurate. 相似文献
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低温氧化是注空气采油及原位燃烧采油技术中的重要化学反应,为深入认识原油在有氧环境下复杂热反应过程中的低温氧化特性,我们采用热重/差热分析法(TG/DTA)研究了线性升温和等温条件下马瑞(Merey)原油的热反应行为。 结果表明,Merey原油在空气及线性升温条件下的受热过程分4个阶段:气化段、低温氧化段、热解段和高温氧化段;相邻阶段的物理、化学主导过程的重叠增加了分析原油热反应特征的难度。 升温速率提高,气化段和低温氧化段的终止温度不变;热解段和高温氧化段的终止温度以及热解段的峰温随升温速率的增加而升高。 N2气与空气下Merey原油的热重/微分热重(TG/DTG)数据对比表明,升温速率越高,空气下的高温氧化段与热解段重叠程度越大,这有利于燃烧但会降低原油采收率。 空气下等温时的TG/DTA结果表明随升温速率增加,升温至300 ℃时的失重率降低,不利于原油轻组分的气化。 反应温度越高,气化过程时间越长,失重分数越大。 Merey原油在低于300℃时低温氧化反应不是主导反应。 相似文献
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压力对深层油藏原油热化学过程的影响尚存在较大争议,为研究其在油藏原油热解成气过程中的作用机理,我们在450℃、5~40 MPa压力下对塔里木原油四组分(饱和分、芳香分、胶质和沥青质)进行了封闭体系的热解实验,通过气相色谱(GC)和气相色谱/质谱(GC/MS)分别对原油四组分热解反应的气体产物及饱和分热解过程的液态产物进行了分析。结果表明,在450℃、24 h及不同压力下,沥青质热解产气率高于胶质、芳香分和饱和分;四组分的气相热解产物中,C1的产率明显高于C2~C5组分。增大压力抑制沥青质、胶质及芳香分的热解产气过程而促进饱和分的热解产气过程。随压力的增大,饱和分热解的液态产物的主峰组分碳数先减小,再增大。压力低于20 MPa时,饱和分热解过程中以裂解反应为主;高于30 MPa时,增大压力有利于缩合反应。研究结果可为认识深层油藏原油的稳定程度及天然气的成因提供一定的理论参考。 相似文献